沉降土体对管道跨越结构应力影响的分析

为了更好地保障长输管道的安全稳定运行，针对长输管道当中的跨越结构进行了应力分析与计算。基于管道跨越结构其结构的特殊性，极容易受到断层、土体塌陷等地质灾害的影响。因此建立了跨越段埋地管道与土壤相互作用的有限元力学模型，分析了30°、40°、50°、60°跨越结构和不同范围土体发生沉降时，管道的应力变化情况。结果显示，当跨越结构中斜管段的角度确定后，便可计算出相应的安全沉降长度；当斜管段角度为50°时，沉降长度控制在13.6m以内，可保证跨越结构不发生塑性变形。通过研究为管道跨越段的安全设计提供了理论依据，该方法可应用在类似的管道跨越结构的应力设计当中。

Analysis on influence to stress of pipeline with crossover structure by soil mass settlement

To better protect the safe and stable operation of long-distance pipeline, the stress on crossover structure of long-distance pipeline was analyzed and calculated. Based on the particularity of its structure, the crossover structure is extremely vulnerable to fault, soil collapse and other geological disasters. Therefore a finite element mechanical model of interactions between the pipeline and soil in the crossover segments of buried pipelines was established, and a detailed analysis on the stress changes of pipeline was conducted when the crossover structure adopted 30, 40, 50 and 60 degrees respectively and the settlement occurred in different range of soil mass. The results showed that the corresponding safe settlement length can be calculated when the angle of inclined pipeline in crossover structures is determined. The settlement length can be controlled within 13.6m, and the plastic deformation will not happen in crossover structures when the angle of inclined pipeline is 50°. It provides a theoretical basis for the safety design of the crossover segment on the buried pipeline, and the method can be applied in the stress design of pipeline with similar crossover structure.